1. Field of the Invention
This invention relates generally to devices which attach structures together but primarily to vehicle trailer hitch assemblies. It is believed that the invention has very practical application in coupling and uncoupling trailers to hauling tractors or other towing vehicles.
2. Description of the Prior Art
Those familiar with the use of trailer hitches are aware of the difficulties encountered when coupling and uncoupling a hitch ball to a female member of a male-female style trailer hitch. Heretofore, coupling and uncoupling these components of the hitch together required precise alignment prior to engagement and disengagement. With more massive payloads and towing vehicles, this task has become particularly difficult, because maneuverability of the towing structures has diminished. For example, this is true for a popular style towing hitch which uses a long, vertical tubular member attached to the receiver or female coupling member of the coupler known as "gooseneck" or "neckover" couplers.
A coupler which assists in engaging and disengaging these hitches would be of great utility. Currently it is a laborious process to hook and unhook the "gooseneck" trailer with heavy tongue loads. For instance, when using a conventional jack it takes about 24 turns of a crank to raise the trailer enough for the coupler to clear the ball. Moreover, when a trailer has a maximum 3,000 pound tongue load, it requires more torque to turn the crank than the average person can generate. To address this problem, trailer manufacturers have generally taken three different approaches.
In the first approach, manufacturers are using jacks with two speed gear boxes. This solves the torque problem, but significantly increases the number of turns required and the number of moving parts in the unit.
In another approach, a few horse and livestock trailer manufacturers are providing electric and electric over hydraulic devices to crank the jack up and down. This is a very high cost alternative which can increase the price of a trailer by as much as 10 percent. This solution also increases the number of moving parts.
These additional moving parts require continuous lubrication to operate efficiently. Moreover, in the corrosive environment in which these couplers often operate, the annoyance and hazard of malfunction is exacerbated. Therefore, a coupler with fewer moving parts would greatly simplify maintenance and reduce the likelihood of malfunction.
Finally, some utility trailer manufacturers have adopted a jack-style coupler. This coupler requires minimum cranking on the jack, however, the operator must crank the jack-style coupler to raise the trailer off the hitch ball instead. Although this process requires fewer turns and far less torque, it is still quite laborious.
What is needed is an inexpensive and uncomplicated coupling device that is easier to use and takes less time and effort to couple and uncouple.